Persistent developmental stuttering as a cortical-subcortical dysfunction: evidence from muscle activation.
BACKGROUND
One contemporary view of stuttering posits that speech disfluencies arise from anomalous speech motor control.


OBJECTIVE
To verify the rest muscle tension and speech reaction time of fluent and stuttering adults.


METHODS
22 adults, divided in two groups: G1--11 fluent individuals; G2--11 stutterers. Electromyography recordings (inferior orbicularis oris) were collected in two different situations: during rest and in a reaction time activity.


RESULTS
The groups were significantly different considering rest muscle tension (G2 higher recordings) and did not differ when considering speech reaction time and muscle activity during speech. There was a strong positive correlation between speech reaction time and speech muscle activity for G2--the longer the speech reaction time, the higher the muscle activity during speech.


CONCLUSIONS
In addition to perceptible episodes of speech disfluency, stutterers exhibit anomalies in speech motor output during fluent speech. Correlations with a possible cortical-subcortical disorder are discussed.
Andrade
Claudia Regina Furquim de
CR
Departament of Physiotherapy, Speech-Language and Hearing Sciences and Occupational Therapy, School of Medicine, University of São Paulo, São Paulo, SP, Brazil. clauan@usp.br
Sassi
Fernanda Chiarion
FC
Juste
Fabiola
F
Mendonça
Lucia Iracema Zanotto de
LI
D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology*; D004576:Electromyography; D005152:Facial Muscles / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D012146:Rest / Q000502:physiology; D013342:Stuttering / Q000503:physiopathology*